nourishment, poverty, and lack of opportunity—some writers have suggested that nothing less than substantial technological, social, and economic changes would provide the conditions under which birth rates can be sufficiently reduced (40). These changes include industrialization, urbanization, and modern market agriculture. In the demographic history of the West such an environment certainly has been associated with sharp declines in birth rates. Urbanization and industrialization, accompanied as they are by rising levels of literacy, better communications, increased economic opportunities, improved health care, lower infant mortality rates, higher status for women, and higher costs of bearing and rearing children, may be necessary to provide the incentives and the means to control population growth. In these terms, a population policy is an overall social and economic development policy.* These two policies would not violate any of our ethical criteria. They would enhance human freedom and encourage responsible community behavior. Indeed, on the face of it they do not violate any of the normative or meta-ethical criteria we have introduced in this essay. Both would increase the elements in the decision-making processes of individual couples that contribute to making the morally best decision. They would increase knowledge of the facts, stimulate the imagination of people concerning the effects of reproductive decisions, and encourage impartiality by fostering more universal loyalties that go beyond one's own interests and passions, and those of one's own group. Gordon and Wyon's proposal has the advantage of introducing a minimum of disruption into a culture. It may, by the same token, be inadequate to induce the requisite behavior without further transformations of the social and economic lot of the people involved. Each of these ethically acceptable population policy proposals relies upon the voluntary decisions of individual couples. Several writers have contended recently that population policies cannot rely upon individual couples pursuing their own benefits to satisfy the needs of society. ' Hardin, for example, has argued that in matters of reproduction individual interests are definitely incompatible with collective interests and, therefore, population growth rates will have to be regulated by society (9). How cogent is this argument? His argument rests on what he calls "the tragedy of the commons." Where a finite amount of grazing land is available to a number of sheepherders, each sheepherder will add sheep to his own flock, ultimately amassing a larger total number of sheep than the land will sustain. Although each individual sheep-herder is aware of this fact, his immediate decisions are determined, nonethe- *See Dudley Kirk, "A New Demographic Transition?" in this volume. tSee, for example, (8, 9, 25, 42).and "The Consequences of Rapid Population Growth," in Vol. I.